title: Interfacial dead-layer effects in Hf-silicate films with Pt or RuO2 gates.
abstract: The interfacial dead-layer (DL) effects at the interfaces between Hf-silicate films and Pt or RuO2 gate metals are examined. The Si content in the Hf-silicate film was controlled to vary the dielectric constant (k). The DL effect was strongly dependent on the k value of the Hf-silicate layer, and was suppressed when the Si content was increased to ∼80% (k ≈ 6). This Si content also coincides with the Fermi level pinning-free composition. Therefore, the optimum high-k gate dielectric structure could be a higher-k layer HfO2 capped with a lower-k layer (k ≈ 6) with minimum thickness (∼1 nm) for the best dielectric performance.
authors.affiliation: Department of Nano Science and Technology, Graduate School of Convergence Science and Technology, Seoul National University, Seoul, Korea.
authors.forename: Hyo Kyeom
authors.initials: HK
authors.lastname: Kim
authors.forename: Il-Hyuk
authors.initials: IH
authors.lastname: Yu
authors.forename: Jae Ho
authors.initials: JH
authors.lastname: Lee
authors.forename: Cheol Seong
authors.initials: CS
authors.lastname: Hwang